package com.mjk.manager.magicapi.core.modules.db.provider;


/**
 * 驼峰命名转换
 *
 * @author mxd
 */
public class CamelColumnMapperProvider implements ColumnMapperProvider {

    @Override
    public String name() {
        return "camel";
    }

    @Override
    public String mapping(String columnName) {
        if (columnName == null) {
            return null;
        }
        columnName = columnName.toLowerCase();
        boolean upperCase = false;
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < columnName.length(); i++) {
            char ch = columnName.charAt(i);
            if (ch == '_') {
                upperCase = true;
            } else if (upperCase) {
                sb.append(Character.toUpperCase(ch));
                upperCase = false;
            } else {
                sb.append(ch);
            }
        }
        return sb.toString();
    }

    @Override
    public String unmapping(String name) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < name.length(); i++) {
            char ch = name.charAt(i);
            if (Character.isUpperCase(ch)) {
                sb.append("_");
            }
            sb.append(Character.toLowerCase(ch));
        }
        return sb.toString();
    }
}
